Our quest to use solar energy started in 1996 when we decided to build a
new home. In our area of Pennsylvania, the sun shines only about 50%
of the time, on average, and the winters are cold. Contractors said that solar
would not work, and the bank refused to lend us money for this type of home.

Fortunately, a good friend believed it could be stainless steel storage tanks and circulator pumps
done and financed our home so that we were able on eBay. These, along with our existing 40-gallon
to build it as designed. Now that our heating bills are oil-fired tank, give us a total capacity of 200 gallons.
less than half those of our neighbors, we’ve proven Assuming the average person uses 20 gallons of hot
the skeptics wrong. water per day, the solar-heated system contributes

For the past 12 years, our south-facing windows sufficient hot water for my wife and myself for four
have saved us a lot on heating costs — but we still days. And when it’s full to capacity, the system con-burned a fair amount of oil to make hot water. In tinues to preheat our well water, reducing the amount
spring 2008, when the price of heating oil was of fuel oil we use to heat water in the 40-gallon tank.
$4.50 a gallon, we searched for a way to use less Since the temperature in our area drops well
oil. Our goal was to use none at all to heat our water below freezing during the winter, I used a closed-during summer, while reducing consumption dra- loop system with food-grade antifreeze. The solar
matically throughout the rest of the year. collector is located at ground level on the hill behind

Our system uses what I call the make-and-hoard my house, to allow me to keep the snow off and to
method: it makes as much hot water as it can on maintain it when necessary (Figures A and B). It
sunny days, and stores it in well-insulated tanks for uses 90 Thermomax pyrex-glass vacuum tubes with
later use. coated copper strips inside each (Figures C and D).

I started by purchasing two inexpensive 80-gallon The vacuum insulates these collector tubes for a